SchemaLock — extract structured JSON data from an invoice PDF or image (vendor, line items, subtotal, tax, total, dates, payment terms). Unlike generic OCR (raw text) or text-only extraction APIs, this takes the raw file directly and validates against source math: line items checked against subtotal/tax/total, dates and currency checked, one automatic retry. If it still fails after that, you aren't charged — settlement is skipped, not just flagged.